Rear view mirrors are utilized to enable vehicle drivers to view objects rearward the vehicle. Traditional rear view mirrors include a mirrored surface mounted to the windshield. Drivers may selectively glance at the mirrored surface and observe the reflection of objects rearward the driver and/or vehicle. This arrangement provides a limited range of visibility to the driver. For example, objects in the rearward portion of the vehicle cabin may obstruct the driver's line of sight. Such objects may include other passengers, head rests, personal items, alumni/“honor role parent” paraphernalia, and the like. Particularly, federal regulations regarding head restraints (e.g., FMVSS 202A) encourage the implementation of larger head rests within the vehicle cabin which further obstruct the driver's field of view. Additionally, reflective or mirror-based vision systems can leave a blind spot in areas not reflected to the driver by the rear view and side view mirrors.
Some contemporary rear visions systems include a two-mode operational platform enabling the driver to select between the mirror-based mode of operation (having the mirrored surface) and a camera-based mode of operation. In the camera-based mode, a camera is mounted in the rearward section of the vehicle, usually the center high-mounted stop lamp or (CHMSL). Video images are relayed from the camera to a display monitor integrated within the rear view mirror or display. Moreover, consumer surveys indicate that similar arrangements, relying on the driver to control such devices, demand a technical savvy that is not commensurate with the technical competency of the average driver. The end result is that such arrangements can be cumbersome to operate for drivers and eventually lead to customer dissatisfaction.
Additionally, both mirror-based and camera-based modes require the driver to adjust their focus to perceive the image(s) and/or information within the display. The human eye is configured to exert variable effort to perceive objects located at different locations with respect to the eye. However, when objects are approximately 2 feet or greater in distance away from the driver's eye, the required exertion of effort to perceive an object is substantially the same as if the object were 7 feet, 20 feet, 100 feet or theoretically an infinite distance away from the driver. When images are displayed within the vehicle cabin at a distance less than 2 feet from the driver's eyes, the driver must switch focus between the fore road and the rear viewing display, i.e., exerting variable levels of effort. This can place unwanted strain on the driver's eyes and lead to customer dissatisfaction.
Therefore, it is desirable to provide a vehicle vision system, at least for rear viewing, that includes a more user friendly control system for switching between various operational modes of the vision system. Moreover, it is desirable to provide a unitary display for any mirror-based and camera-based modes of operation. Additionally, it would be beneficial to provide a vehicle vision system that has the flexibility of providing video images from cameras mounted within the interior as well as the exterior of the vehicle. Further, it is desirable to provide a vision system that displays images at a distance greater that two feet away from the vehicle driver's eyes so as to minimize user eye strain. Further still, it would be advantageous to provide the driver with a display having a focal distance greater than the distance from the driver's eyes to the rearview mirror area of the vehicle. The teachings hereinbelow extend to those embodiments which fall within the scope of the appended claims, regardless of whether they accomplish one or more of the above-mentioned needs.